structures + functions

Question 1

Lamina (leaf blade) :

Answer 1

broadness provides large surface area for maximum absorption of light; Thinness provides short diffusion distance for gases and enables light to reach all mesophyll cells.

Question 2

Petiole (leaf stalk) :

Answer 2

holds leaf in position to absorb maximum light energy

Question 3

Cuticle:

Answer 3

Waxiness reduces water loss through evaporation; transparent for light to reach cells within.

Question 4

stomata:

Answer 4

opens in the presence of light, allowing carbon dioxide to diffuse in and oxygen to diffuse out of the leaf.

Question 5

chloroplasts in all mesophyll cells:

Answer 5

chlorophyll absorbs and transforms light energy to chemical energy used in the manufacture of sugars.

Question 6

more chloroplasts in upper palisade tissue:

Answer 6

more light energy can be absorbed near the leaf surface.

Question 7

air spaces in spongy mesophyll:

Answer 7

allows rapid diffusion of carbon dioxide in and out of the mesophyll cells.

Question 8

leaf veins situated close to the mesophyll cells:

Answer 8

xylem transports water and mineral salts to the mesophyll cells; phloem transports sugars away from the leaf.